Apparatus for grinding



Sept 1949- A. E. HAMILTON 2,483,277

APPARATUS FOR GRINDING Filed Feb. 11, 1946 3 Shee tS-Sheet l INVENTOR 74 FRED f/qma raw.

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f p 1949- A. E. HAMILTON APPARATUS FOR GRINDING 3 sheets sheet 2 Filed Feb. 11, 1946 lNVENTOR H1. nae-'0 6. Hana. 01v.

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ms ATTORNEY p 1949- A. E. HAMILTON 2,483,277

APPARATUS FOR GRINDING Filed Feb. 11, 1946 5 s Sheets-Sheet 5 lNVENTOR H4 FEA'O f. Hanan. 7-0.

ATTORNEY Patented Sept. 27, 1949 UNITED S TAT? ES F FIiCE APPARATUS FOR -GRINDING Alf-recl- E.. Hamilton, ,Eittsburgh, Pat

Application February 11, 1946, Serial No; 646,833"

3 llaims.

Myi invention relates more particularly to r the grinding of metal strips andi sheets iniorder to give a smoother and cleaner finish thereto than they' have when. received from: reducing. rolls, either in hot rolling; or cold rolling operations;

In; rolling or grinding strip or sheet metal to a: desired gaugeor finish; and. particularlywhen it is=given. a: number of'passes through rolls or atrain-of rolls, particles of'the metal become-arrrangedv along: lines parallel to: the direction; of rolling and grinding, thus forming what are known as grairrlines. These lines are objectionable in that in the subsequent bending of the metal aboutaxes parallel to the direction in which the-sheet was rolledon ground,.as?fon*example, in the forming of channels; the grainalines frequently cause erackingof the metal along lines at the zones of'bending; The-grinding referred to is usually a rough grinding or snagging? operatiomusually in a direction,longitudinally of'the strip; to remove rough defects.

Usually, any subsequent grinding operations are-performed upon the metal bygrinding wheels or the like whoseaxes are.tr-ansverse to the paths of travel of the material through the reducing rolls; and past the grinding: wheels. This: tends to; increase: the undesirable: grain". line structure onconditionzof the sheets.

I have found that if the final grinding operations are performed by abrasive elements moving in a direction generally transverse to the longitudinal axes of the strips or sheets, and hence generally transverse to the grain lines that are developed during the rolling or rough grinding operations, the grain lines are broken up or largely eliminated, with the result that danger of cracking of the sheets during subsequent shaping operations is largely avoided.

My invention, therefore, has for its object the provision of a method and means whereby the said grain lines can be broken or interrupted in a simple and convenient manner.

Apparatus suitable for use in practicing my invention is shown in the accompanying drawings, wherein Figure 1 is a side elevational view of a grinding machine; Fig. 2 is a sectional plan view thereof with certain of the parts omitted for clarity; Fig. 3 is a face view of a portion of the apparatus of Fig. 1, and Fig. 4 shows a modification of the apparatus of Fig. 1, suitable for operating upon sheets.

Referring first to Figs. 1 to 3, I show a roll stand -5 in which abrasive rolls or drums 6 and 1 are mounted. The roll 1 is driven by a [belt or series of V-belts 8, from a motor 9 carried by a 2- bracket 4 that is secured to the-rollstand, while the roll fi' is drivenby abelt it from another motor not here shown but which may suitably be mount'edin' the'other endof the roll stand 5 5 ina manner si-milar'to-that shown in-my Patent 2358,5722 The surfacing drums 61- willpref erably be driven in opposite directions sothat their abrasive surfaces will move ingenerally parallel directions at the roll pass. Ihe motors 10 which drive therolls may be of'the reversible type so that they can drive the rolls alsoindirectionsopposite to those indicated by the arrows, as-may be desired, or depending upon ithedirection in which the strip or sheets isbeing fed.

The drums 6- and T are here shown a having abrasive surfacing grains on helically-wound strips II which may suitably be placed on the rolls in-the manner showninmy said'patent, but itwill be understood. that abrasive roll's of cylindrical block form canbe used if desired.

As shown in Fig. 1-; the roll'stand 5 is supported on a circularlyarranged anti-friction bearing I 2 and -iias awor-m gear i 3 withwhich a worm M has driving-engagement, the-shaft of thew-orm M being mounted in fixed-bearings at P5 and having a crank ifi' by whichit may be turned to rotate the roll stand on a vertical axis. Since the'm-otors' for driving the surfacing drums'iare al'swcarried by the-r011- stand, there-Will be no disturbances of the driving connections of these motors and the drums during such adjustments of the roll stand.

In Fig. 1, the metal strip I 8 is being drawn from a coil at l9 past the drums *6 and l and recoiled at 20, motors 2| and 22 being provided for moving the strip in either direction, since when it has been passed through the surfacing rolls in one direction, it may be desired to give it a second pass in the opposite direction. Idler 4Q guide rolls 23 and 24 are provided for directing the strip to guide tables 25 and 26 that have upstanding flanges at their edges as shown more clearly in Fig. 3, to prevent lateral displacement of the strip by reason of the diagonal pull of the 5 surfacing rolls thereon.

In order to effect the grinding operation in a direction somewhat crosswise of the strip and to thereby break up the grain lines present in the strip, the worm gear will be turned to place the grinding rolls in approximately the angular position shown in Fig. 2, so that the abrasion is in a direction generally crosswise of the strip. When the strip has been moved past the grinding rolls in one direction, the worm gear can be operated to reverse the angularity of the grinding rolls with respect to the strip and the strip then passed through the machine in the opposite direction. This reversal of angularity not only will result in changing the direction of grinding on the strip and hence more effectively breaks up the grain lines, but any tendency for a pattern to be formed on the strip surfaces by reason of the helically-wound abrasive strips is reduced.

Referring now to Fig. 4, I show apparatus more particularly designed for the surfacing of sheets instead of strips, in order to break up the grain lines. In this arrangement, the surfacing rolls 21 and 28 will be mounted for angular adjustment as are the rolls 6 and I, but feed rollers 29 and 30 are provided to move the sheets across guide tables 3| and 32 into the roll pass, these guide tables being constructed similarly to the guides 25 and 26, to prevent lateral shifting of the sheets in the roll pass.

In some instances, it will be necessary to grind only one surface of each sheet in which case two sheets or strips can be passed through the machine in matched relationship so that the upper surfacing drum will grind the exposed surface of the top sheet and the lower drum grind the exposed lower surface of the bottom sheet.

When a strip has been ground by diagonallyplaced rolls having abrasive of a certain grain size, it may subsequently be passed between diagonally-placed abrasive rolls having grit of smaller grain size. The peripheral speed of the surfacing rolls will preferably be much greater than the speed at which the strip or sheets are moved. For example, the strip may have a travel of only 25 feet to 100 ft. per minute, while the peripheral speed of the rolls may be 3000 feet to 5000 ft. per minute.

The placing of the abrasive rolls with their axes diagonal to the path of travel of the work is advantageous even where there is no problem of grain lines in the work, particularly when the material is passed between abrasive rolls disposed at one angle and then between abrasive rolls disposed at a different angle, since such procedure may result in avoiding pronounced lines of abrasion in directions longitudinally of the material.

While certain of the accompanying claims refer to the work piece as being in the form of a strip,

it will be understood that they contemplate also the operation upon sheets.

I claim as my invention:

1. Grinding apparatus comprising means for directing work pieces in a given path of travel, a roll stand positioned adjacent to said path, an abrasive roll carried by said stand and mounted on an axis that extends generally transverse to said path, and means for rotatably adjusting the roll stand to shift the roll axis in a plane parallel to the plane of the material, to thereby change the angularity of the roll axis.

2. Grinding apparatus comprising means for directing work pieces in a given path of travel, a roll stand positioned adjacent to said path, an abrasive roll carried by said stand and mounted on an axis that extends generally transverse to said path, and means for rotatably adjusting the roll stand to shift the roll axis in a plane parallel to the plane of the material, to diagonal positions at either side of a position transverse to said path, to' thereby change the angularity of the roll axis.

3. Grinding apparatus comprising means. for

. directing work pieces in a given path of travel,

a roll stand positioned adjacent to said'path, a pair of abrasive rolls respectively positioned on the stand above and. below the said path and in position to engage the work pieces, and means for adjusting the roll stand about an axis perpendicular to the work pieces.

ALFRED E. HAMILTON.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PAXTEN'IS Number Name Date 633,722 Koenig Sept. 26, 1899 743,911 Muller Nov. 10, 1903 1,006,881 Russell Oct. 24, 1911 2,269,197 Hamilton Jan. 6, 1942 FOREIGN PATENTS Number Country Date 23,333 Austria Mar. 10, 1906 49,730 Germany Nov. 22, 1889 

